• Title/Summary/Keyword: cell infection

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DISEASE DIAGNOSED AND DESCRIBED BY NIRS

  • Tsenkova, Roumiana N.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1031-1031
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    • 2001
  • The mammary gland is made up of remarkably sensitive tissue, which has the capability of producing a large volume of secretion, milk, under normal or healthy conditions. When bacteria enter the gland and establish an infection (mastitis), inflammation is initiated accompanied by an influx of white cells from the blood stream, by altered secretory function, and changes in the volume and composition of secretion. Cell numbers in milk are closely associated with inflammation and udder health. These somatic cell counts (SCC) are accepted as the international standard measurement of milk quality in dairy and for mastitis diagnosis. NIR Spectra of unhomogenized composite milk samples from 14 cows (healthy and mastitic), 7days after parturition and during the next 30 days of lactation were measured. Different multivariate analysis techniques were used to diagnose the disease at very early stage and determine how the spectral properties of milk vary with its composition and animal health. PLS model for prediction of somatic cell count (SCC) based on NIR milk spectra was made. The best accuracy of determination for the 1100-2500nm range was found using smoothed absorbance data and 10 PLS factors. The standard error of prediction for independent validation set of samples was 0.382, correlation coefficient 0.854 and the variation coefficient 7.63%. It has been found that SCC determination by NIR milk spectra was indirect and based on the related changes in milk composition. From the spectral changes, we learned that when mastitis occurred, the most significant factors that simultaneously influenced milk spectra were alteration of milk proteins and changes in ionic concentration of milk. It was consistent with the results we obtained further when applied 2DCOS. Two-dimensional correlation analysis of NIR milk spectra was done to assess the changes in milk composition, which occur when somatic cell count (SCC) levels vary. The synchronous correlation map revealed that when SCC increases, protein levels increase while water and lactose levels decrease. Results from the analysis of the asynchronous plot indicated that changes in water and fat absorptions occur before other milk components. In addition, the technique was used to assess the changes in milk during a period when SCC levels do not vary appreciably. Results indicated that milk components are in equilibrium and no appreciable change in a given component was seen with respect to another. This was found in both healthy and mastitic animals. However, milk components were found to vary with SCC content regardless of the range considered. This important finding demonstrates that 2-D correlation analysis may be used to track even subtle changes in milk composition in individual cows. To find out the right threshold for SCC when used for mastitis diagnosis at cow level, classification of milk samples was performed using soft independent modeling of class analogy (SIMCA) and different spectral data pretreatment. Two levels of SCC - 200 000 cells/$m\ell$ and 300 000 cells/$m\ell$, respectively, were set up and compared as thresholds to discriminate between healthy and mastitic cows. The best detection accuracy was found with 200 000 cells/$m\ell$ as threshold for mastitis and smoothed absorbance data: - 98% of the milk samples in the calibration set and 87% of the samples in the independent test set were correctly classified. When the spectral information was studied it was found that the successful mastitis diagnosis was based on reviling the spectral changes related to the corresponding changes in milk composition. NIRS combined with different ways of spectral data ruining can provide faster and nondestructive alternative to current methods for mastitis diagnosis and a new inside into disease understanding at molecular level.

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Pulmonary Toxicity Following High-Dose Chemotherapy With Peripheral Blood Stem Cell Transplantation (고용량 항암화학요법 후에 발생한 폐손상)

  • Lee, Sun-Min;Park, Kwang-Joo;Oh, Yoon-Jung;Cheong, Seong-Cheoll;Hwang, Sung-Chul;Lee, Yi-Hyung;Kim, Hyun-Soo;Lim, Ho-Yeong;Kim, Hugh-Chul;Yim, Hyun-Ee;Hahn, Myung-Ho
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.1
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    • pp.77-89
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    • 1999
  • Background: High-dose chemotherapy is increasingly employed in many refractory malignant diseases. This therapy has been reported to increase response rate and survival benefits but it is also associated with higher treatment-related morbidity and mortality. We evaluated clinical characteristics and course of the pulmonary toxicity following high-dose chemotherapy with peripheral blood stem cell transplantation. Methods: Ninety-seven patients who had received high-dose chemotherapy with peripheral blood stem cell transplantation were evaluated. Five patients who developed lung lesions which were not related to infection nor primary malignant disease underwent transbronchial lung biopsy. The patients' clinical characteristics, treatments, and prognosis were reviewed retrospectively. Results: Five patients(5.1%) developed idiopathic pneumonia syndrome. The high dose chemotherapy regimens employed were cyclophosphamide, BCNU, and cisplatin in 3 cases, one case of BCNU, etoposide, Ara-C, and cyclophosphamide combination, and a regimen consisting of BCNU, etoposide, Ara-C, and melphalan. The total dose of BCNU used was 300-400 mg/$m^2$ and that of cyclophosphsmide was 6,000 mg/$m^2$. All of 5 patients received radiation therapy before this treatment. After an average duration of 14 weeks (4-26 weeks) of high-dose chemotherapy, patients developed cough, dyspnea and fever. The chest X-rays showed bilateral diffuse infiltration in 3 cases and the focal infiltration in the other 2 cases. All the patients received corticosteroid therapy as a treatment for the lung lesions. Two of them progressed to acute respiratory distress syndrome and died. Three patients recovered without residual lung lesion but one of them died of dilated cardiomyopathy. Conclusion: High-dose chemotherapy with peripheral blood stem cell transplantation especially which containing BCNU regimen may develop idiopathic pneumonia syndrome related to pulmonary toxicity and corticosteroid therapy may be bel1eficial in some cases.

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Evaluation of the Cell-Mediated Immunity in Treatment Failure Pulmonary Tuberculosis (치료실패 폐결핵 환자의 세포성면역반응에 관한 연구)

  • Park, Jeong-Kyu;Park, Jang-Seo;Kim, Hwa-Jung;Jo, Eun-Gyeong;Min, Dul-Lel;Lim, Jae-Hyun;Suhr, Ji-Won;Paik, Tae-Hyun
    • Tuberculosis and Respiratory Diseases
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    • v.47 no.1
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    • pp.13-25
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    • 1999
  • Background: Ineffective cell-mediated immune response in human tuberculosis is associated with a depressed Thl cytokine response and reduced production of IFN-$\gamma$. Most persons infected with Mycobacterium tuberculosis are healthy tuberculin reactors with protective immunity, but a minority with ineffective immunity develop extensive pulmonary tuberculosis. The cell-mediated immune response is an important aspect of host resistance to mycobacterial infection and is believed to be tightly regulated by a balance between Th1 cytokines including IFN-$\gamma$, IL-12, IL-18, regulated on activation, normal T cell expressed and secreted (RANTES) and Th2 counterparts such as IL-4, monocyte chemoattractant protein-l (MCP-l). Methods: Proliferation and mRNA expression of IFN-$\gamma$, RANTES and MCP-l by RT-PCR in peripheral blood mononuclear cells (PBMCs) in response to in vitro stimulation with mycobacterial antigens were compared in pulmonary tuberculosis patients with cured and treatment failure and in tuberculin-positive and tuberculin-negative healthy subjects. Results: Defective proliferative responsiveness to aqueous TSP antigen was involved with treatment failure tuberculosis patients. Aqueous TSP antigen-induced IFN-$\gamma$ and RANTES mRNA expression was decreased in treatment failure tuberculosis patients compared with healthy tuberculin reactors and cured tuberculosis patients (23.1 % versus 90.0% for IFN-$\gamma$ and 46.2% versus 70.0% versus 46.2% for RANTES). The frequency of MCP-l mRNA expression to aqueous TSP antigen in treatment failure tuberculosis patients was greater than in healthy tuberculin reactors and cured tuberculosis patients (76.9% versus 40.0%). Conclusion: The increasing expression of MCP-1 mRNA in response to aqueous TSP antigen might be predicted to favor Th1 responses and restricted Th1 responses in treatment failure of pulmonary tuberculosis.

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The First Newborn Screening Study of T-Cell Receptor Excision Circle and κ-Deleting Recombination Excision Circle for Severe Combined Immunodeficiency in Korea: A Pilot Study (국내 최초 T-Cell Receptor Excision Circle과 κ-Deleting Recombination Excision Circle 신생아 선별검사에 관한 연구)

  • Son, Sohee;Kang, Ji-Man;Kim, Jong Min;Sung, Sein;Kim, Yi-Seoul;Lee, Haejeong;Kim, BitA Reum;Lee, Yeon Kyoung;Ko, Sun Young;Shin, Son Moon;Kim, Yae-Jean
    • Pediatric Infection and Vaccine
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    • v.24 no.3
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    • pp.134-140
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    • 2017
  • Purpose: Severe combined immunodeficiency (SCID) is the most serious form of primary immunodeficiency. Infants with SCID are susceptible to life-threatening infections. To establish newborn screening for SCID in Korea, we performed a screening test for T-cell receptor excision circle (TREC) and ${\kappa}$-deleting recombination excision circle (KREC) in neonates and investigated the awareness of SCID among their parents. Methods: Collections of dried blood spots from neonates and parent surveys were performed at the Samsung Medical Center and Cheil General Hospital & Women's Healthcare Center in Korea. The amplification crossing point (Cp) value <37.0 was defined as TREC/KRECpositive based on cutoff values from measuring multiplex real-time polymerase chain reaction. A Cp value >39.0 was defined as negative. Results: For TREC/KREC screening, 141 neonates were enrolled; 63 (44.7%) were male. One hundred forty neonates (99.3%) had positive TREC/KREC results at the time of the initial test; 82.3% and 75.9% were positive and 17.0% and 23.4% were weakly positive for TREC and KREC, respectively. In one neonate (0.7%), the initial TREC/KREC test result was negative. However, repeated tests obtained and confirmed a positive result. For an awareness survey, 168 parents were engaged. Only 2% of parents (3/168) knew that the newborn screening test for SCID had been introduced and performed in other countries. Eighty-four percent of parents (141/168) replied that nationwide newborn SCID screening should be performed in Korean newborns. Conclusions: In this study, newborn SCID screening was performed along with assessment of public awareness of the SCID test in Korea. The study results showed that newborn SCID screening can be readily applied for clinical use at a relatively low cost in Korea.

Enzymatic Assessment of $2-Hydroxyethyl-{\beta}-undecenate$ Purified from Cumin (Cuminum cymium L.) Seed for Anti-periodontitis (Cumin(Cuminum cymium L.) seed로부터 정제한 $2-hydroxyethyl-{\beta}-undecenate$의 항치주염 효과의 효소학적 평가)

  • Ryu, Il-Hwan;Kang, Eun-Ju;Lee, Kap-Sang;Park, Chung-Soon
    • Korean Journal of Food Science and Technology
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    • v.39 no.6
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    • pp.669-675
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    • 2007
  • The present study was conducted to explore the anti-inflammatory action of $2-hydroxyethyl-{\beta}-undecenate$ (HPS) purified from Cumin (Cuminum cymium L.) seed against periodontitis. From the study in which human leukocyte was employed to detect the inhibiting effects of 5-lipokygenase and cyclooxygenase, enzymes generating carriers of infection like $LTB_4$ and PGs, as well as of collagenase and elastase, organ-destroying enzymes, following conclusions could be drawn: HPS was found to inhibit leukotrien $B_4$ biosynthesis by stimulating more than 97% of human polymorphonuclear leukocyte (PMNL) with addition of $5\;{\times}\;10^{-2}\;M$ when $IC_{50}$ was set at $2\;{\times}\;10^{-4}\;M$. Ninety-two percent of enzyme activation turned out to be inhibited when $5\;{\times}\;10^{-2}\;M$ was added in a test to prove inhibiting effects of HPS against activation of PMNL 5-lipoxygenase from homogeneous humans and purified 5-lipoxygenase on the market. Besides, $IC_{50}$ for enzyme activation was valued at $2.5\;{\times}\;10^{-4}\;M$, while the value of $IC_{50}$ for purified 5-lipoxygenase was $2.3\;{\times}\;10^{-4}\;M$. The $IC_{50}$ values of COX-activated leukocyte and purified collagenase were $5.1\;{\times}\;10^{-4}\;M$ and $2.3\;{\times}\;10^{-4}\;M$, respectively. Moreover, the value of $IC_{50}$ for activation of leukocyte collagenase was $2\;{\times}\;10^{-3}\;M$, whereas that for purified collagenase was $5\;{\times}\;10^{-2}\;M$. In case of leukocyte elastase, addition of $5\;{\times}\;10^{-2}\;M$ inhibited its activation by 66%. In case of purified one, however, activation of enzyme was inhibited by 25% with addition of $5\;{\times}\;10^{-2}\;M$. Furthermore, the $IC_{50}$ value for activation of leukocyte elastase was revealed to be $7.5\;{\times}\;10^{-3}\;M$. From the virulence test with human gingiva cell, it was shown that, on the second day of cultivation, 47.83% of the cell had been activated when HPS was added by $5\;{\times}\;10^{-2}\;M$. Even the addition of HPS by $1\;{\times}\;10^{-2}\;M$ featured 68.53% of cell activation, suggesting relatively strong toxicity of the substance against gingiva cell.

Evaluation of Commercial Complementary DNA Synthesis Kits for Detecting Human Papillomavirus (인유두종바이러스 검출을 위한 상용화된 cDNA 합성 키트의 평가)

  • Yu, Kwangmin;Park, Sunyoung;Chang, Yunhee;Hwang, Dasom;Kim, Geehyuk;Kim, Jungho;Kim, Sunghyun;Kim, Eun-Joong;Lee, Dongsup
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.3
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    • pp.309-315
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    • 2019
  • Cervical cancer is the fourth most common malignant neoplasm in women worldwide. Most cases of cervical cancer are caused by an infection by the human papillomavirus. Molecular diagnostic methods have emerged to detect the HPV for sensitivity, specificity, and objectivity. In particular, real-time PCR has been introduced to acquire a more sensitive target DNA or RNA. RNA extraction and complementary DNA synthesis are proceeded before performing real-time PCR targeting RNA. To identify an adequate and sensitive cDNA synthesis kit, this study evaluated the two commonly used kits for cDNA synthesis. The results show that the $R^2$ and efficiency (%) of the two cDNA synthesis kits were similar in the cervical cancer cell lines. On the other hand, the Takara kit compared to Invitrogen kit showed P<0.001 in the $10^2$ and $10^3$ SiHa cell count. The Takara kit compared to the Invitrogen kit showed P<0.001 in the $10^1$ and $10^2$ HeLa cell count. Furthermore, 8, 4, 2, 1, and 0.5 ml of forty exfoliated cell samples were used to compare the cDNA synthesis kits. The Takara kit compared to the Invitrogen kit showed P<0.01 in 8, 4, and 1 ml and P<0.05 in 0.5 mL. The study was performed to identify the most appropriate cDNA synthesis kit and suggests that a cDNA synthesis kit could affect the real-time PCR results.

Transfer, Cryopreservation and Production of Bovine Embryos Cultured in Serum-Free System (Serum-Free Medium에서 배양한 한우 배의 내동성과 이식)

  • Im, Y.-J.;Kim, J.-H.;Song, H.-B.;Jung, Y.-G.
    • Journal of Embryo Transfer
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    • v.19 no.2
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    • pp.133-145
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    • 2004
  • Serum-contain is commoly used for the production of in vitro-derived bovine embryos. However, were biological activity of serum varies from lot to lot, time consuming to choose better serum with good quality and risks of virus, bacteria and mycoplasma infection. This study established serum-free culture systems of in vitro embryo development to efficiently obtain a large number of blastocysts from ovaries of Hanwoo and oocytes maturation, cell number, tlerance of cryopreservation. Secondly, serum-contain medium is suspected of contributing to the large calf size, dystocia, cersarean sections, calf mortality and confirmed these blastocysts are high quality in terms of cyotolerance, high rates of pregancy and normal birth. For these reasons, Culture media (IVMD101 and IVD101) designed specifically for the preimplantation bovine embryo are rather simplistic, being based on salt solutions with additional energy substrates and growth factors. An improved serum-free medium (IVMD101) was developed for bovine oocytes maturation in vitro. Proportions of embryos developing to the blastocyst stage cultured in both IVD101(32.4%) and IVD101(34.5%) serum-free media were higher than in TCM199+10% FBS(12.4%) serumcontaining medium. Futhermore, the cell numbers per blastosyst obtained in the serum-free media were superior to those of blastocysts developed in serum-supplemented medium. Also, cell numbers of blastocysts obtained in the serum-free media were similar with blastocysts derived in vivo. Survival rate blastocysts after 24 hr incubation after thawing, the blastocysts cultured in both IVD101(94.5%) and IVD101(95.8%) serum-free media were higher than in TCM199+10% FBS (52.5%) serum-containing medium. After 72 hr incubation after thawing, hatching rates of blastocysts developed in IVD101(78.4%) and IVMD101(83.7%) were sighnificantly higher than that developed in the serum-supplemented medium(32.0%). The pregnancy rates almost not different between fresh blastocysts(38.2%) and frozen blastocysts(34.9%). The results suggested that the improved serum-free media(IVMD101 and IVD101) offer several advantages over culture in serum-cotaining medium, including increased rates of blastocyst formation and high cel numbers. Additionally, the survival and hatching rates of embryos product in serum-free media after post-thaw culture were superior to those of embryos produced in the serum-containg medium and useful for the production of high quality bovine embryos for cryo-preservation. These improved serum-free media are beneficial not only for the study of the mechanisms of early embryogenesis but also for mass production of good quality embryos for embryo transfer, cloning and transgenesis.

Viral Patterns and Clincal Analysis of Acute Respiratory Tract Infections of Children in Korea(September, 1998~August, 2002) (바이러스에 의한 소아 급성 하기도 감염의 유행 및 임상양상(1998년 9월~2002년 8월))

  • Lee, Su-Jin;Park, Eun-Young;Oh, Phil-Soo;Lee, Kon-Hee;Kim, Kwang-Nam;Lee, Kyu-Man
    • Pediatric Infection and Vaccine
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    • v.10 no.1
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    • pp.102-113
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    • 2003
  • Purpose : Acute respiratory tract infections are the most common illnesses in children. The great majority of these infections involving lower respiratory tracts infections(LRTI) are caused by respiratory viruses such as respiratory syncytial virus(RSV), parainfluenza virus (PIV), influenza virus(INF), adenovirus(ADV), etc. Our purpose of this study was to examine the seasonal occurrence, clinical and laboratory features of each viral infections. Methods : Nasopharyngeal aspirates(NPA) were collected from 913 hospitalized children on the first day of admission. They were all admitted to Hangang Sacred Heart hospital and diagnosed as LRTIs. The study period was from September 1998 to August 2002. Specimens were inoculated onto HEp-2 cell, LLC-MK2 cell and MDCK cell. Viruses were detected by immunofluorescent method performed at day 10 postinoculation. Respiratory viruses were detected in 251(27%) cases. Medical records of 208 cases diagnosed as acute LRTIs were all taken reviewed and analyzed. Results : The identified pathogens were RSV 122 cases(58%), PIV 30 cases(14%), INFA 20 cases(10%), INFB 21 cases(11%) and ADV 15 cases(7%) during the study period. Outbreaks of RSV infections occurred every year but mostly on December, 1998 and November, 1999. LRTIs by PIV and ADV occurred during all seasons of the year. INFA was isolated moslty on March, 1999 and January, 2000. INFB infections occurred largely on April, 2002. The clinical diagnoses were bronchiolitis 88 cases(43%), pneumonia 87 cases(42%), croup 19 cases(9%) and tracheobronchitis 14 cases(6%). Common symptoms and signs were cough, rhinorrhea, sputum and fever. WBC counts in peripheral blood showed normal findings in 123 cases(59%). Each viral infections also showed some differences in auscultatory findings and chest X-ray findings. Conclusion : We learned that viruses are one of the major and important etiologic agents of acute LRTIs of children in Korea. However, we still need to find out more about its characteristic clinical features and continue studying on their seasonal occurrence to focus on their management and also prevention.

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A Study on the Manufacture of the Artificial Cardiac Tissue Valve (생체판의 제작 및 실험)

  • Kim, Hyoung-Mook;Song, Yo-Jun;Sohn, Kwang-Hyun
    • Journal of Chest Surgery
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    • v.12 no.4
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    • pp.383-394
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    • 1979
  • Treatment of valvular heart disease with valve replacement has been one of the most popular procedures in cardiac surgery recently. Although, first effort was directed toward the prosthetic valve, it soon became popular that bioprosthesis, the valvular xenograft, was prefered in the majority cases. Valvular xenograft has some superiority to the artificial prosthetic valve in some points of thromboembolism and hemolytic anemia, and it also has some inferiority of durability, immunologic reaction and resistance to Infection. Tremendous efforts were made to cover the inferiority with several methods of collection, preservation, and valve mounting of the porcine valve or pericardium of the calf, and also with surgical technique of the valvular xenograft replacement. Auther has collected 320 porcine aortic valves immediately after slaughter, and aortic cusps were coapted with cotton balls in the Valsalva sinuses to protect valve deformity after immersion in the Hanks' solution, and oxidation, cross-linking and reduction procedures were completed after the proposal of Carpentier in 1972. Well preserved aortic valves were suture mounted in the hand-made tissue valve frame of 19, 21, and 23 mm J.d., and also in the prosthetic vascular segment of 19 mm Ld. with 4-0 nylon sutures after careful trimming of the aortic valves. Completed valves were evaluated with bacteriologic culture, pressure tolerance test with tolerane gauge, valve durability test in the saline glycerine mixed solution with tolerance test machine in the speed of 300 rpm, and again with pathologic changes to obtain following results: 1. Bacteriologic culture of the valve tissue in five different preservation method for two weeks revealed excellent and satisfactory result in view of sterilization including 0.65% glutaraldehyde preservation group for one week bacteriologic culture except one tissue with Citobacter freundii in 75% ethanol preserved group. 2. Pressure tolerance test was done with an apparatus composed of V-connected manometer and pressure applicator. Tolerable limit of pressure was recorded when central leaking jet of saline was observed. Average pressure tolerated in each group was 168 mmHg in glutaraldehyde, 128 mmHg in formaldehyde, 92 mmHg in Dakin's solution, 48 mmHg in ethylene oxide gas, and 26 mmHg in ethanol preserved group in relation to the control group of Ringer's 90 mmHg respectively. 3. Prolonged durability test was performed in the group of frame mounted xenograft tissue valve with 300 up-and-down motion tolerance test machine/min. There were no specific valve deformity or wearing in both 19, 21, and 23 mm valves at the end of 3 months (actually 15 months), and another 3 months durability test revealed minimal valve leakage during pressure tolerance test due to contraction deformity of the non-coronary cusp at the end of 6 months (actually 30 months) in the largest 23 mm group. 4. Histopathologic observation was focussed in three view points, endothelial cell lining, collagen and elastic fiber destructions in each preservation methods and long durable valvular tolerance test group. Endothel ial cell lining and collagen fiber were well preserved in the glutaraldehyde and formaldehyde treated group with minimal destruction of elastic fiber. In long durable tolerance test group revealed complete destruction of the endothelial cell lining with minimal destruction of the collagen and elastic fiber in 3 month and 6 month group in relation to the time and severity. In conclusion, porcine xenograft treated after the proposal of Carpentier in 1972 and preserved in the glutaraldehyde solution was the best method of collection, preservation and valve mounting. Pressure tolerance and valve motion tolerance test, also, revealed most satisfactory results in the glutaraldehyde preserved group.

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Ag Ion Substituted HAp Coatings on Ti-6Al-4V Substrate by IBAD and It's Bactericidal Effect (Ti 합금표면의 항균성 HAp Coating에 관한 연구)

  • Jung, Moon-Young;Kim, Taik-Nam;Kim, Yun-Jong;Yim, Hyuk-Jun;Kim, Jong-Ock;Lim, Dae-young;Kim, Sun-Ok
    • The Journal of Engineering Research
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    • v.3 no.1
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    • pp.189-197
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    • 1998
  • Hyeroxyapatite(HAp) which has good biocompatibility was made by Wet Chemical Process. The surface of Ti-6Al-4V, coated with HAp by lon Beam Assisted Deposition (IBAD), was treated with 5ppm, 10ppm, 20ppm, and 100ppm of $AgNO_3$ solution. In this Ag impregnation process, $Ca^{2+}$ of HAp was substituted with $Ag^+$ of $AgNO_3$. In this study, the antimicrobial effect and biocompatibility of Ti-6Al-4V alloy which was coated with Ag-HAp were examined. The antimicrobial test was carried out with two kinds of bacteria(P. Aeruginosa, S. Epidermidis), which are highly infectious in a transplanting operation of implant materials. As a result of the test, it was observed that Ti-6Al-4V alloy which was treated by 20ppm of $AgNO_3$ solution has good biocompatibility. In order to observe the antimicrobial mechanism of $Ag^+$, E. coli which is the most common bacterium was treated by Ag-HAp. Then cell morphology of E. coli was observed by the transmission electron microscope(TEM). The destruction of cell wall and cytoplasm of E. coil were observed. A black spot appeared in the cytoplasm was analyzed by energy dispersive analysis X-ray (EDAX) and it showed a small amount of $Ag^+$. Thus, it was proved that $Ag^+$ destroys bacteria effectively and Ti-6Al-4V alloy which was impregnate with Ag ion show antimicrobial effect on infection bacteria.

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